Currently, a rotary playground equipment premising that a few users (mean children) play together has been developed.
For example, the sandbox where a plurality of users plays with is disclosed in Japanese Unexamined Pat. App. Pub. No. H10-85459, and an air dome used in events is disclosed in Japanese Unexamined Pat. App. Pub. No. 2000-204795.
Other than above technique, generally, the playground equipment which is developed for playing with for a plurality of users, is common in amusement grounds or a theme park.